How 'stable' must you be to have a cat?

I've always wanted a cat. I live in a huge coliving and I know I could have one there, but I might move at some point. I've never taken the step because I want to make sure I have a stable home, but as long as I don't own anything (which might be impossible ever given the prices in Stockholm), I don't feel that it would be fair to have one.

At the same time... It would save one from a shelter and life is hard to predict right? What do you think?